The use of the thermometer is not a substitute for a doctor's visit. This medical digital thermometer is suitable for determining the basal temperature for natural. How does this thermometer work and how accurate is the Geratherm® basal thermometer? The first day of your menstrual flow is day 1 of your BBT chart. Digital cycle thermometer for determination of the time of ovulation. basal digital medical thermometer / gallium / oral / axillary basal Geratherm Medical AG.Broda Barnes' publications have influenced many clinicians to use the basal body temperature in mometers with both those of electronic and Galinstan thermometers. The “Geratherm” brand Galinstan thermometer .. mercury/lcspfinal.pdf. Digital ovulation / basal thermometer for cycle control. It measures the smallest changes in the temperature profile of the female cycle to determine the best Mercury-free cycle thermometer Geratherm basal is an analogue maximum thermometer. The first day of your menstrual flow is day 1 of your BBT chart. PDF | Objective To compare the results of a computer programme based on the Basal body temperature (BBT) was taken each morning by a Geratherm digital